Today, therapies exist that involve the administration at precisely defined locations of very small amounts of a pharmaceutical over the course of minutes or even hours. These therapies include, for example, viral vectors for gene therapy, or protein suppression therapies. As some of these pharmaceuticals can be extremely expensive, waste of the pharmaceutical is to be minimized. Waste of the pharmaceutical may occur, for example, from dead space within the delivery system, such as the volumes inherent in catheters, needles, syringes and the like. For practical reasons, such as when delivering the pharmaceutical to brain tissue, the pharmaceutical cannot be diluted up to higher volumes. Hence, precisely controlled delivery of small amounts of a pharmaceutical with minimal waste is greatly desired for such therapies.